The release of that spectrum has made it possible for a new technology to emerge — the pieces are coming together for what has become known as “super Wi-Fi.”
“It’s a new way to make efficient use of the spectrum,” said Julius Knapp, chief of the FCC’s Office of Engineering and Technology. Unlicensed spectrum in the UHF band could signal a new approach to spectrum management. If all goes well with the release of TV white space, more chunks of the spectrum may be released for unlicensed use as well, Knapp said.
Coming of Age
Unlicensed spectrum means anyone with an invention or idea has an open field to play on, and super Wi-Fi is just what it sounds like — a longer-ranging, faster version of standard Wi-Fi. It makes use of the empty spaces between TV channels normally set aside to prevent interference. Because TV white spaces are at lower frequencies than Wi-Fi, signals, they provide better propagation and penetration through obstacles such as buildings or trees — the mortal enemies of standard Wi-Fi hot spots. The result is wireless broadband speeds that are available for several miles surrounding a single access point.Often, people view technologies like super Wi-Fi as emerging overnight, but it doesn’t usually happen that way — there’s an adjustment period during which the technology finds its potential, said Jon Peha, an engineering professor at Carnegie Mellon University. Peha is one of the researchers responsible for developing Wi-Fi in the early ’90s, before it had a name.
“It’s an exciting time,” he said. “We have just made it possible to deploy an entirely different technology, one that has a lot of potential.” Improved Wi-Fi hot spots, particularly for use in rural areas as a substitute for traditional broadband, may be one of the biggest applications for super Wi-Fi. But the exciting part, Peha said, is not knowing how the technology will evolve.
“It is the FCC’s job to make spectrum available, and it’s the entrepreneur’s job to find uses for it. That’s exactly what should happen and exactly what is happening,” Peha said. “The entrepreneur and researcher in me is very excited with what kinds of systems might emerge.”
New Systems
Already there is no shortage of companies seeking ways to make the most of the newly available TV white space.In Houston, an experimental super Wi-Fi hot spot, funded by the National Science Foundation, was developed by Rice University professor Edward Knightly and Will Reed, CEO and president of the nonprofit organization Technology For All. “The way the whole white space thing evolved was helping underserved communities,” Reed said. “We’re figuring out ways to level the playing field. White space is certainly a big part of that.”
From both a financial and philanthropic standpoint, Reed said super Wi-Fi looks promising — it’s more cost-effective than the alternatives, and it’s possible to reach more people with less equipment and fewer technical problems.
“Our usage has just gone up like crazy,” he said. “Clearly it’s meeting a need in the community. We just need the resources to meet that need.”
Knightly agreed that the project was going well. “We’re exploring questions about what the next generation of wireless protocols and networks looks like.”
Spectrum previously dedicated to television is now serving Internet, and it could just be the beginning. Rural areas typically don’t have many TV channels, so super Wi-Fi works well there. But in urban areas, where channels are more tightly packed, a shift may prove necessary — away from giving broadcasters access to the UHF band and toward using that space for high-speed Internet, Knightly said. “Policy will ultimately decide if this takes off.”
Picking Up Static
Because super Wi-Fi uses spectrum once reserved to prevent TV interference, television broadcasters have expressed concerns about what this means for their industry. The National Association of Broadcasters (NAB) has been actively protecting its territory since seeing the first signs of unlicensed white space several years ago. Dennis Wharton, vice president of communications at NAB, said the association isn’t against super Wi-Fi, but warned that any interference caused to TV stations would tremendously hurt broadcasters. “We don’t want to sound like we’re being anti-technology. We’re not,” Wharton said. But broadcasters have made it clear that they don’t want their livelihood marginalized by any technology, new or old.It’s unclear how worried broadcasters should be, but it appears they’re not being forgotten. Pending legislation would allow current holders of UHF band licenses to hold “incentive auctions” — so broadcasters may soon be able to lease or share their spectrum with Internet providers to allow broadband more access to the UHF band.
Exactly how things will turn out for TV broadcasters is unclear, but change is coming.
Protecting incumbent spectrum holders like broadcasters is one goal of a white-space database developed by Peter Stanforth, CTO and co-founder of Spectrum Bridge. The problem with using UHF white space is that it’s not uniformly available around the country; there are different TV stations and public safety systems from state to state and from county to county using parts of the spectrum.
“What the database does, generically, is it keeps track of who’s using what and, more importantly, where there’s unused space,” Stanforth said. “There’s an awful lot of spectrum around the country that sits idle. This could fix the spectrum crisis. You could say the crisis has been artificially engineered, because of the way we distribute spectrum.”
The database is configured to allow spectrum to be used in the most efficient manner, he said. A lot of unused spectrum is dedicated to public safety functions that are rarely used. The white space database coordinates radios that want to use white spaces, but still gives public safety priority — in the event of an emergency, public safety gets spectrum back until the event has ended.
The FCC tested Spectrum Bridge’s database for 45 days, ending Nov. 2. The company is now asking the FCC to certify Spectrum Bridge as the official steward of white space.
“The basic technology and rules work very well,” Stanforth said. “A lot of people are still very confused and leery of what’s going on. Their big fear is that we don’t protect their interests. Protecting those who were there first is a big part of my job, as is persuading people that this is a good thing for everyone. White space will add more spectrum, more bandwidth. Their worst fears are unlikely to materialize.”
Wireless technology |is transforming, he said. Instead of auctioning spectrum to the highest bidder, the country is moving toward a pay-per-use model. “It used to be that whoever owned the towers was the king, but that changed,” Stanforth said. Now, holding onto spectrum is as futile as holding onto towers.
